The present invention relates to a light emitting element array, a semiconductor device, a manufacturing method thereof, a printing head, and an image forming apparatus. The present invention is applicable to, for example, an electrophotographic image forming apparatus such as a printer.
A conventional semiconductor device capable of emitting light is constituted by an optical semiconductor element array chip bonded to a semiconductor integrated circuit substrate having electrode terminals. The optical semiconductor element array chip and the semiconductor integrated circuit substrate are connected using wires (see, Japanese Application Publication No. 2004-207323).
In the conventional semiconductor device, it is necessary to provide bonding pads for bonding the wires. Therefore, it is difficult to reduce sizes of the optical semiconductor element array chip and the semiconductor integrated circuit substrate.
In order to solve this problem, Japanese Application Publication No. 2004-207323 discloses a semiconductor device in which a semiconductor thin-film layer including at least one optical semiconductor element is bonded to a planarized region on a surface of a semiconductor integrated circuit substrate. The optical semiconductor element is electrically connected to electrode terminals of the semiconductor integrated circuit substrate by photolithographic process. With such a configuration, regions for the bonding pads can be eliminated, and a chip width can be reduced. Therefore, a material of the semiconductor element (herein referred to as a semiconductor element material) such as GaAs or AlGaAs can be saved, and manufacturing cost can be reduced.
However, since the semiconductor element material such as GaAs or AlGaAs is expensive, it is still desirable to save the semiconductor element material. Therefore, it is still desirable to manufacture as many semiconductor thin-film layers as possible from the semiconductor element material of a certain area.
For this reason, there is a demand for technology capable of achieving reduction in manufacturing cost.